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Merge branch 'topic/hda' into for-linus
[mirror_ubuntu-jammy-kernel.git] / kernel / sysctl.c
1 /*
2 * sysctl.c: General linux system control interface
3 *
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
12 * Horn.
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
16 * Wendling.
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
19 */
20
21 #include <linux/module.h>
22 #include <linux/mm.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/security.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/kmemcheck.h>
31 #include <linux/smp_lock.h>
32 #include <linux/fs.h>
33 #include <linux/init.h>
34 #include <linux/kernel.h>
35 #include <linux/kobject.h>
36 #include <linux/net.h>
37 #include <linux/sysrq.h>
38 #include <linux/highuid.h>
39 #include <linux/writeback.h>
40 #include <linux/hugetlb.h>
41 #include <linux/initrd.h>
42 #include <linux/key.h>
43 #include <linux/times.h>
44 #include <linux/limits.h>
45 #include <linux/dcache.h>
46 #include <linux/syscalls.h>
47 #include <linux/vmstat.h>
48 #include <linux/nfs_fs.h>
49 #include <linux/acpi.h>
50 #include <linux/reboot.h>
51 #include <linux/ftrace.h>
52 #include <linux/security.h>
53 #include <linux/slow-work.h>
54 #include <linux/perf_counter.h>
55
56 #include <asm/uaccess.h>
57 #include <asm/processor.h>
58
59 #ifdef CONFIG_X86
60 #include <asm/nmi.h>
61 #include <asm/stacktrace.h>
62 #include <asm/io.h>
63 #endif
64
65 static int deprecated_sysctl_warning(struct __sysctl_args *args);
66
67 #if defined(CONFIG_SYSCTL)
68
69 /* External variables not in a header file. */
70 extern int C_A_D;
71 extern int print_fatal_signals;
72 extern int sysctl_overcommit_memory;
73 extern int sysctl_overcommit_ratio;
74 extern int sysctl_panic_on_oom;
75 extern int sysctl_oom_kill_allocating_task;
76 extern int sysctl_oom_dump_tasks;
77 extern int max_threads;
78 extern int core_uses_pid;
79 extern int suid_dumpable;
80 extern char core_pattern[];
81 extern int pid_max;
82 extern int min_free_kbytes;
83 extern int pid_max_min, pid_max_max;
84 extern int sysctl_drop_caches;
85 extern int percpu_pagelist_fraction;
86 extern int compat_log;
87 extern int latencytop_enabled;
88 extern int sysctl_nr_open_min, sysctl_nr_open_max;
89 #ifndef CONFIG_MMU
90 extern int sysctl_nr_trim_pages;
91 #endif
92 #ifdef CONFIG_RCU_TORTURE_TEST
93 extern int rcutorture_runnable;
94 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
95
96 /* Constants used for minimum and maximum */
97 #ifdef CONFIG_DETECT_SOFTLOCKUP
98 static int sixty = 60;
99 static int neg_one = -1;
100 #endif
101
102 static int zero;
103 static int __maybe_unused one = 1;
104 static int __maybe_unused two = 2;
105 static unsigned long one_ul = 1;
106 static int one_hundred = 100;
107
108 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
109 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
110
111 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
112 static int maxolduid = 65535;
113 static int minolduid;
114 static int min_percpu_pagelist_fract = 8;
115
116 static int ngroups_max = NGROUPS_MAX;
117
118 #ifdef CONFIG_MODULES
119 extern char modprobe_path[];
120 extern int modules_disabled;
121 #endif
122 #ifdef CONFIG_CHR_DEV_SG
123 extern int sg_big_buff;
124 #endif
125
126 #ifdef CONFIG_SPARC
127 #include <asm/system.h>
128 #endif
129
130 #ifdef CONFIG_SPARC64
131 extern int sysctl_tsb_ratio;
132 #endif
133
134 #ifdef __hppa__
135 extern int pwrsw_enabled;
136 extern int unaligned_enabled;
137 #endif
138
139 #ifdef CONFIG_S390
140 #ifdef CONFIG_MATHEMU
141 extern int sysctl_ieee_emulation_warnings;
142 #endif
143 extern int sysctl_userprocess_debug;
144 extern int spin_retry;
145 #endif
146
147 #ifdef CONFIG_BSD_PROCESS_ACCT
148 extern int acct_parm[];
149 #endif
150
151 #ifdef CONFIG_IA64
152 extern int no_unaligned_warning;
153 extern int unaligned_dump_stack;
154 #endif
155
156 #ifdef CONFIG_RT_MUTEXES
157 extern int max_lock_depth;
158 #endif
159
160 #ifdef CONFIG_PROC_SYSCTL
161 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
162 void __user *buffer, size_t *lenp, loff_t *ppos);
163 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
164 void __user *buffer, size_t *lenp, loff_t *ppos);
165 #endif
166
167 static struct ctl_table root_table[];
168 static struct ctl_table_root sysctl_table_root;
169 static struct ctl_table_header root_table_header = {
170 .count = 1,
171 .ctl_table = root_table,
172 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
173 .root = &sysctl_table_root,
174 .set = &sysctl_table_root.default_set,
175 };
176 static struct ctl_table_root sysctl_table_root = {
177 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
178 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
179 };
180
181 static struct ctl_table kern_table[];
182 static struct ctl_table vm_table[];
183 static struct ctl_table fs_table[];
184 static struct ctl_table debug_table[];
185 static struct ctl_table dev_table[];
186 extern struct ctl_table random_table[];
187 #ifdef CONFIG_INOTIFY_USER
188 extern struct ctl_table inotify_table[];
189 #endif
190 #ifdef CONFIG_EPOLL
191 extern struct ctl_table epoll_table[];
192 #endif
193
194 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
195 int sysctl_legacy_va_layout;
196 #endif
197
198 extern int prove_locking;
199 extern int lock_stat;
200
201 /* The default sysctl tables: */
202
203 static struct ctl_table root_table[] = {
204 {
205 .ctl_name = CTL_KERN,
206 .procname = "kernel",
207 .mode = 0555,
208 .child = kern_table,
209 },
210 {
211 .ctl_name = CTL_VM,
212 .procname = "vm",
213 .mode = 0555,
214 .child = vm_table,
215 },
216 {
217 .ctl_name = CTL_FS,
218 .procname = "fs",
219 .mode = 0555,
220 .child = fs_table,
221 },
222 {
223 .ctl_name = CTL_DEBUG,
224 .procname = "debug",
225 .mode = 0555,
226 .child = debug_table,
227 },
228 {
229 .ctl_name = CTL_DEV,
230 .procname = "dev",
231 .mode = 0555,
232 .child = dev_table,
233 },
234 /*
235 * NOTE: do not add new entries to this table unless you have read
236 * Documentation/sysctl/ctl_unnumbered.txt
237 */
238 { .ctl_name = 0 }
239 };
240
241 #ifdef CONFIG_SCHED_DEBUG
242 static int min_sched_granularity_ns = 100000; /* 100 usecs */
243 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
244 static int min_wakeup_granularity_ns; /* 0 usecs */
245 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
246 #endif
247
248 static struct ctl_table kern_table[] = {
249 #ifdef CONFIG_SCHED_DEBUG
250 {
251 .ctl_name = CTL_UNNUMBERED,
252 .procname = "sched_min_granularity_ns",
253 .data = &sysctl_sched_min_granularity,
254 .maxlen = sizeof(unsigned int),
255 .mode = 0644,
256 .proc_handler = &sched_nr_latency_handler,
257 .strategy = &sysctl_intvec,
258 .extra1 = &min_sched_granularity_ns,
259 .extra2 = &max_sched_granularity_ns,
260 },
261 {
262 .ctl_name = CTL_UNNUMBERED,
263 .procname = "sched_latency_ns",
264 .data = &sysctl_sched_latency,
265 .maxlen = sizeof(unsigned int),
266 .mode = 0644,
267 .proc_handler = &sched_nr_latency_handler,
268 .strategy = &sysctl_intvec,
269 .extra1 = &min_sched_granularity_ns,
270 .extra2 = &max_sched_granularity_ns,
271 },
272 {
273 .ctl_name = CTL_UNNUMBERED,
274 .procname = "sched_wakeup_granularity_ns",
275 .data = &sysctl_sched_wakeup_granularity,
276 .maxlen = sizeof(unsigned int),
277 .mode = 0644,
278 .proc_handler = &proc_dointvec_minmax,
279 .strategy = &sysctl_intvec,
280 .extra1 = &min_wakeup_granularity_ns,
281 .extra2 = &max_wakeup_granularity_ns,
282 },
283 {
284 .ctl_name = CTL_UNNUMBERED,
285 .procname = "sched_shares_ratelimit",
286 .data = &sysctl_sched_shares_ratelimit,
287 .maxlen = sizeof(unsigned int),
288 .mode = 0644,
289 .proc_handler = &proc_dointvec,
290 },
291 {
292 .ctl_name = CTL_UNNUMBERED,
293 .procname = "sched_shares_thresh",
294 .data = &sysctl_sched_shares_thresh,
295 .maxlen = sizeof(unsigned int),
296 .mode = 0644,
297 .proc_handler = &proc_dointvec_minmax,
298 .strategy = &sysctl_intvec,
299 .extra1 = &zero,
300 },
301 {
302 .ctl_name = CTL_UNNUMBERED,
303 .procname = "sched_child_runs_first",
304 .data = &sysctl_sched_child_runs_first,
305 .maxlen = sizeof(unsigned int),
306 .mode = 0644,
307 .proc_handler = &proc_dointvec,
308 },
309 {
310 .ctl_name = CTL_UNNUMBERED,
311 .procname = "sched_features",
312 .data = &sysctl_sched_features,
313 .maxlen = sizeof(unsigned int),
314 .mode = 0644,
315 .proc_handler = &proc_dointvec,
316 },
317 {
318 .ctl_name = CTL_UNNUMBERED,
319 .procname = "sched_migration_cost",
320 .data = &sysctl_sched_migration_cost,
321 .maxlen = sizeof(unsigned int),
322 .mode = 0644,
323 .proc_handler = &proc_dointvec,
324 },
325 {
326 .ctl_name = CTL_UNNUMBERED,
327 .procname = "sched_nr_migrate",
328 .data = &sysctl_sched_nr_migrate,
329 .maxlen = sizeof(unsigned int),
330 .mode = 0644,
331 .proc_handler = &proc_dointvec,
332 },
333 {
334 .ctl_name = CTL_UNNUMBERED,
335 .procname = "timer_migration",
336 .data = &sysctl_timer_migration,
337 .maxlen = sizeof(unsigned int),
338 .mode = 0644,
339 .proc_handler = &proc_dointvec_minmax,
340 .strategy = &sysctl_intvec,
341 .extra1 = &zero,
342 .extra2 = &one,
343 },
344 #endif
345 {
346 .ctl_name = CTL_UNNUMBERED,
347 .procname = "sched_rt_period_us",
348 .data = &sysctl_sched_rt_period,
349 .maxlen = sizeof(unsigned int),
350 .mode = 0644,
351 .proc_handler = &sched_rt_handler,
352 },
353 {
354 .ctl_name = CTL_UNNUMBERED,
355 .procname = "sched_rt_runtime_us",
356 .data = &sysctl_sched_rt_runtime,
357 .maxlen = sizeof(int),
358 .mode = 0644,
359 .proc_handler = &sched_rt_handler,
360 },
361 {
362 .ctl_name = CTL_UNNUMBERED,
363 .procname = "sched_compat_yield",
364 .data = &sysctl_sched_compat_yield,
365 .maxlen = sizeof(unsigned int),
366 .mode = 0644,
367 .proc_handler = &proc_dointvec,
368 },
369 #ifdef CONFIG_PROVE_LOCKING
370 {
371 .ctl_name = CTL_UNNUMBERED,
372 .procname = "prove_locking",
373 .data = &prove_locking,
374 .maxlen = sizeof(int),
375 .mode = 0644,
376 .proc_handler = &proc_dointvec,
377 },
378 #endif
379 #ifdef CONFIG_LOCK_STAT
380 {
381 .ctl_name = CTL_UNNUMBERED,
382 .procname = "lock_stat",
383 .data = &lock_stat,
384 .maxlen = sizeof(int),
385 .mode = 0644,
386 .proc_handler = &proc_dointvec,
387 },
388 #endif
389 {
390 .ctl_name = KERN_PANIC,
391 .procname = "panic",
392 .data = &panic_timeout,
393 .maxlen = sizeof(int),
394 .mode = 0644,
395 .proc_handler = &proc_dointvec,
396 },
397 {
398 .ctl_name = KERN_CORE_USES_PID,
399 .procname = "core_uses_pid",
400 .data = &core_uses_pid,
401 .maxlen = sizeof(int),
402 .mode = 0644,
403 .proc_handler = &proc_dointvec,
404 },
405 {
406 .ctl_name = KERN_CORE_PATTERN,
407 .procname = "core_pattern",
408 .data = core_pattern,
409 .maxlen = CORENAME_MAX_SIZE,
410 .mode = 0644,
411 .proc_handler = &proc_dostring,
412 .strategy = &sysctl_string,
413 },
414 #ifdef CONFIG_PROC_SYSCTL
415 {
416 .procname = "tainted",
417 .maxlen = sizeof(long),
418 .mode = 0644,
419 .proc_handler = &proc_taint,
420 },
421 #endif
422 #ifdef CONFIG_LATENCYTOP
423 {
424 .procname = "latencytop",
425 .data = &latencytop_enabled,
426 .maxlen = sizeof(int),
427 .mode = 0644,
428 .proc_handler = &proc_dointvec,
429 },
430 #endif
431 #ifdef CONFIG_BLK_DEV_INITRD
432 {
433 .ctl_name = KERN_REALROOTDEV,
434 .procname = "real-root-dev",
435 .data = &real_root_dev,
436 .maxlen = sizeof(int),
437 .mode = 0644,
438 .proc_handler = &proc_dointvec,
439 },
440 #endif
441 {
442 .ctl_name = CTL_UNNUMBERED,
443 .procname = "print-fatal-signals",
444 .data = &print_fatal_signals,
445 .maxlen = sizeof(int),
446 .mode = 0644,
447 .proc_handler = &proc_dointvec,
448 },
449 #ifdef CONFIG_SPARC
450 {
451 .ctl_name = KERN_SPARC_REBOOT,
452 .procname = "reboot-cmd",
453 .data = reboot_command,
454 .maxlen = 256,
455 .mode = 0644,
456 .proc_handler = &proc_dostring,
457 .strategy = &sysctl_string,
458 },
459 {
460 .ctl_name = KERN_SPARC_STOP_A,
461 .procname = "stop-a",
462 .data = &stop_a_enabled,
463 .maxlen = sizeof (int),
464 .mode = 0644,
465 .proc_handler = &proc_dointvec,
466 },
467 {
468 .ctl_name = KERN_SPARC_SCONS_PWROFF,
469 .procname = "scons-poweroff",
470 .data = &scons_pwroff,
471 .maxlen = sizeof (int),
472 .mode = 0644,
473 .proc_handler = &proc_dointvec,
474 },
475 #endif
476 #ifdef CONFIG_SPARC64
477 {
478 .ctl_name = CTL_UNNUMBERED,
479 .procname = "tsb-ratio",
480 .data = &sysctl_tsb_ratio,
481 .maxlen = sizeof (int),
482 .mode = 0644,
483 .proc_handler = &proc_dointvec,
484 },
485 #endif
486 #ifdef __hppa__
487 {
488 .ctl_name = KERN_HPPA_PWRSW,
489 .procname = "soft-power",
490 .data = &pwrsw_enabled,
491 .maxlen = sizeof (int),
492 .mode = 0644,
493 .proc_handler = &proc_dointvec,
494 },
495 {
496 .ctl_name = KERN_HPPA_UNALIGNED,
497 .procname = "unaligned-trap",
498 .data = &unaligned_enabled,
499 .maxlen = sizeof (int),
500 .mode = 0644,
501 .proc_handler = &proc_dointvec,
502 },
503 #endif
504 {
505 .ctl_name = KERN_CTLALTDEL,
506 .procname = "ctrl-alt-del",
507 .data = &C_A_D,
508 .maxlen = sizeof(int),
509 .mode = 0644,
510 .proc_handler = &proc_dointvec,
511 },
512 #ifdef CONFIG_FUNCTION_TRACER
513 {
514 .ctl_name = CTL_UNNUMBERED,
515 .procname = "ftrace_enabled",
516 .data = &ftrace_enabled,
517 .maxlen = sizeof(int),
518 .mode = 0644,
519 .proc_handler = &ftrace_enable_sysctl,
520 },
521 #endif
522 #ifdef CONFIG_STACK_TRACER
523 {
524 .ctl_name = CTL_UNNUMBERED,
525 .procname = "stack_tracer_enabled",
526 .data = &stack_tracer_enabled,
527 .maxlen = sizeof(int),
528 .mode = 0644,
529 .proc_handler = &stack_trace_sysctl,
530 },
531 #endif
532 #ifdef CONFIG_TRACING
533 {
534 .ctl_name = CTL_UNNUMBERED,
535 .procname = "ftrace_dump_on_oops",
536 .data = &ftrace_dump_on_oops,
537 .maxlen = sizeof(int),
538 .mode = 0644,
539 .proc_handler = &proc_dointvec,
540 },
541 #endif
542 #ifdef CONFIG_MODULES
543 {
544 .ctl_name = KERN_MODPROBE,
545 .procname = "modprobe",
546 .data = &modprobe_path,
547 .maxlen = KMOD_PATH_LEN,
548 .mode = 0644,
549 .proc_handler = &proc_dostring,
550 .strategy = &sysctl_string,
551 },
552 {
553 .ctl_name = CTL_UNNUMBERED,
554 .procname = "modules_disabled",
555 .data = &modules_disabled,
556 .maxlen = sizeof(int),
557 .mode = 0644,
558 /* only handle a transition from default "0" to "1" */
559 .proc_handler = &proc_dointvec_minmax,
560 .extra1 = &one,
561 .extra2 = &one,
562 },
563 #endif
564 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
565 {
566 .ctl_name = KERN_HOTPLUG,
567 .procname = "hotplug",
568 .data = &uevent_helper,
569 .maxlen = UEVENT_HELPER_PATH_LEN,
570 .mode = 0644,
571 .proc_handler = &proc_dostring,
572 .strategy = &sysctl_string,
573 },
574 #endif
575 #ifdef CONFIG_CHR_DEV_SG
576 {
577 .ctl_name = KERN_SG_BIG_BUFF,
578 .procname = "sg-big-buff",
579 .data = &sg_big_buff,
580 .maxlen = sizeof (int),
581 .mode = 0444,
582 .proc_handler = &proc_dointvec,
583 },
584 #endif
585 #ifdef CONFIG_BSD_PROCESS_ACCT
586 {
587 .ctl_name = KERN_ACCT,
588 .procname = "acct",
589 .data = &acct_parm,
590 .maxlen = 3*sizeof(int),
591 .mode = 0644,
592 .proc_handler = &proc_dointvec,
593 },
594 #endif
595 #ifdef CONFIG_MAGIC_SYSRQ
596 {
597 .ctl_name = KERN_SYSRQ,
598 .procname = "sysrq",
599 .data = &__sysrq_enabled,
600 .maxlen = sizeof (int),
601 .mode = 0644,
602 .proc_handler = &proc_dointvec,
603 },
604 #endif
605 #ifdef CONFIG_PROC_SYSCTL
606 {
607 .procname = "cad_pid",
608 .data = NULL,
609 .maxlen = sizeof (int),
610 .mode = 0600,
611 .proc_handler = &proc_do_cad_pid,
612 },
613 #endif
614 {
615 .ctl_name = KERN_MAX_THREADS,
616 .procname = "threads-max",
617 .data = &max_threads,
618 .maxlen = sizeof(int),
619 .mode = 0644,
620 .proc_handler = &proc_dointvec,
621 },
622 {
623 .ctl_name = KERN_RANDOM,
624 .procname = "random",
625 .mode = 0555,
626 .child = random_table,
627 },
628 {
629 .ctl_name = KERN_OVERFLOWUID,
630 .procname = "overflowuid",
631 .data = &overflowuid,
632 .maxlen = sizeof(int),
633 .mode = 0644,
634 .proc_handler = &proc_dointvec_minmax,
635 .strategy = &sysctl_intvec,
636 .extra1 = &minolduid,
637 .extra2 = &maxolduid,
638 },
639 {
640 .ctl_name = KERN_OVERFLOWGID,
641 .procname = "overflowgid",
642 .data = &overflowgid,
643 .maxlen = sizeof(int),
644 .mode = 0644,
645 .proc_handler = &proc_dointvec_minmax,
646 .strategy = &sysctl_intvec,
647 .extra1 = &minolduid,
648 .extra2 = &maxolduid,
649 },
650 #ifdef CONFIG_S390
651 #ifdef CONFIG_MATHEMU
652 {
653 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
654 .procname = "ieee_emulation_warnings",
655 .data = &sysctl_ieee_emulation_warnings,
656 .maxlen = sizeof(int),
657 .mode = 0644,
658 .proc_handler = &proc_dointvec,
659 },
660 #endif
661 {
662 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
663 .procname = "userprocess_debug",
664 .data = &sysctl_userprocess_debug,
665 .maxlen = sizeof(int),
666 .mode = 0644,
667 .proc_handler = &proc_dointvec,
668 },
669 #endif
670 {
671 .ctl_name = KERN_PIDMAX,
672 .procname = "pid_max",
673 .data = &pid_max,
674 .maxlen = sizeof (int),
675 .mode = 0644,
676 .proc_handler = &proc_dointvec_minmax,
677 .strategy = sysctl_intvec,
678 .extra1 = &pid_max_min,
679 .extra2 = &pid_max_max,
680 },
681 {
682 .ctl_name = KERN_PANIC_ON_OOPS,
683 .procname = "panic_on_oops",
684 .data = &panic_on_oops,
685 .maxlen = sizeof(int),
686 .mode = 0644,
687 .proc_handler = &proc_dointvec,
688 },
689 #if defined CONFIG_PRINTK
690 {
691 .ctl_name = KERN_PRINTK,
692 .procname = "printk",
693 .data = &console_loglevel,
694 .maxlen = 4*sizeof(int),
695 .mode = 0644,
696 .proc_handler = &proc_dointvec,
697 },
698 {
699 .ctl_name = KERN_PRINTK_RATELIMIT,
700 .procname = "printk_ratelimit",
701 .data = &printk_ratelimit_state.interval,
702 .maxlen = sizeof(int),
703 .mode = 0644,
704 .proc_handler = &proc_dointvec_jiffies,
705 .strategy = &sysctl_jiffies,
706 },
707 {
708 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
709 .procname = "printk_ratelimit_burst",
710 .data = &printk_ratelimit_state.burst,
711 .maxlen = sizeof(int),
712 .mode = 0644,
713 .proc_handler = &proc_dointvec,
714 },
715 #endif
716 {
717 .ctl_name = KERN_NGROUPS_MAX,
718 .procname = "ngroups_max",
719 .data = &ngroups_max,
720 .maxlen = sizeof (int),
721 .mode = 0444,
722 .proc_handler = &proc_dointvec,
723 },
724 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
725 {
726 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
727 .procname = "unknown_nmi_panic",
728 .data = &unknown_nmi_panic,
729 .maxlen = sizeof (int),
730 .mode = 0644,
731 .proc_handler = &proc_dointvec,
732 },
733 {
734 .procname = "nmi_watchdog",
735 .data = &nmi_watchdog_enabled,
736 .maxlen = sizeof (int),
737 .mode = 0644,
738 .proc_handler = &proc_nmi_enabled,
739 },
740 #endif
741 #if defined(CONFIG_X86)
742 {
743 .ctl_name = KERN_PANIC_ON_NMI,
744 .procname = "panic_on_unrecovered_nmi",
745 .data = &panic_on_unrecovered_nmi,
746 .maxlen = sizeof(int),
747 .mode = 0644,
748 .proc_handler = &proc_dointvec,
749 },
750 {
751 .ctl_name = CTL_UNNUMBERED,
752 .procname = "panic_on_io_nmi",
753 .data = &panic_on_io_nmi,
754 .maxlen = sizeof(int),
755 .mode = 0644,
756 .proc_handler = &proc_dointvec,
757 },
758 {
759 .ctl_name = KERN_BOOTLOADER_TYPE,
760 .procname = "bootloader_type",
761 .data = &bootloader_type,
762 .maxlen = sizeof (int),
763 .mode = 0444,
764 .proc_handler = &proc_dointvec,
765 },
766 {
767 .ctl_name = CTL_UNNUMBERED,
768 .procname = "bootloader_version",
769 .data = &bootloader_version,
770 .maxlen = sizeof (int),
771 .mode = 0444,
772 .proc_handler = &proc_dointvec,
773 },
774 {
775 .ctl_name = CTL_UNNUMBERED,
776 .procname = "kstack_depth_to_print",
777 .data = &kstack_depth_to_print,
778 .maxlen = sizeof(int),
779 .mode = 0644,
780 .proc_handler = &proc_dointvec,
781 },
782 {
783 .ctl_name = CTL_UNNUMBERED,
784 .procname = "io_delay_type",
785 .data = &io_delay_type,
786 .maxlen = sizeof(int),
787 .mode = 0644,
788 .proc_handler = &proc_dointvec,
789 },
790 #endif
791 #if defined(CONFIG_MMU)
792 {
793 .ctl_name = KERN_RANDOMIZE,
794 .procname = "randomize_va_space",
795 .data = &randomize_va_space,
796 .maxlen = sizeof(int),
797 .mode = 0644,
798 .proc_handler = &proc_dointvec,
799 },
800 #endif
801 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
802 {
803 .ctl_name = KERN_SPIN_RETRY,
804 .procname = "spin_retry",
805 .data = &spin_retry,
806 .maxlen = sizeof (int),
807 .mode = 0644,
808 .proc_handler = &proc_dointvec,
809 },
810 #endif
811 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
812 {
813 .procname = "acpi_video_flags",
814 .data = &acpi_realmode_flags,
815 .maxlen = sizeof (unsigned long),
816 .mode = 0644,
817 .proc_handler = &proc_doulongvec_minmax,
818 },
819 #endif
820 #ifdef CONFIG_IA64
821 {
822 .ctl_name = KERN_IA64_UNALIGNED,
823 .procname = "ignore-unaligned-usertrap",
824 .data = &no_unaligned_warning,
825 .maxlen = sizeof (int),
826 .mode = 0644,
827 .proc_handler = &proc_dointvec,
828 },
829 {
830 .ctl_name = CTL_UNNUMBERED,
831 .procname = "unaligned-dump-stack",
832 .data = &unaligned_dump_stack,
833 .maxlen = sizeof (int),
834 .mode = 0644,
835 .proc_handler = &proc_dointvec,
836 },
837 #endif
838 #ifdef CONFIG_DETECT_SOFTLOCKUP
839 {
840 .ctl_name = CTL_UNNUMBERED,
841 .procname = "softlockup_panic",
842 .data = &softlockup_panic,
843 .maxlen = sizeof(int),
844 .mode = 0644,
845 .proc_handler = &proc_dointvec_minmax,
846 .strategy = &sysctl_intvec,
847 .extra1 = &zero,
848 .extra2 = &one,
849 },
850 {
851 .ctl_name = CTL_UNNUMBERED,
852 .procname = "softlockup_thresh",
853 .data = &softlockup_thresh,
854 .maxlen = sizeof(int),
855 .mode = 0644,
856 .proc_handler = &proc_dosoftlockup_thresh,
857 .strategy = &sysctl_intvec,
858 .extra1 = &neg_one,
859 .extra2 = &sixty,
860 },
861 #endif
862 #ifdef CONFIG_DETECT_HUNG_TASK
863 {
864 .ctl_name = CTL_UNNUMBERED,
865 .procname = "hung_task_panic",
866 .data = &sysctl_hung_task_panic,
867 .maxlen = sizeof(int),
868 .mode = 0644,
869 .proc_handler = &proc_dointvec_minmax,
870 .strategy = &sysctl_intvec,
871 .extra1 = &zero,
872 .extra2 = &one,
873 },
874 {
875 .ctl_name = CTL_UNNUMBERED,
876 .procname = "hung_task_check_count",
877 .data = &sysctl_hung_task_check_count,
878 .maxlen = sizeof(unsigned long),
879 .mode = 0644,
880 .proc_handler = &proc_doulongvec_minmax,
881 .strategy = &sysctl_intvec,
882 },
883 {
884 .ctl_name = CTL_UNNUMBERED,
885 .procname = "hung_task_timeout_secs",
886 .data = &sysctl_hung_task_timeout_secs,
887 .maxlen = sizeof(unsigned long),
888 .mode = 0644,
889 .proc_handler = &proc_dohung_task_timeout_secs,
890 .strategy = &sysctl_intvec,
891 },
892 {
893 .ctl_name = CTL_UNNUMBERED,
894 .procname = "hung_task_warnings",
895 .data = &sysctl_hung_task_warnings,
896 .maxlen = sizeof(unsigned long),
897 .mode = 0644,
898 .proc_handler = &proc_doulongvec_minmax,
899 .strategy = &sysctl_intvec,
900 },
901 #endif
902 #ifdef CONFIG_COMPAT
903 {
904 .ctl_name = KERN_COMPAT_LOG,
905 .procname = "compat-log",
906 .data = &compat_log,
907 .maxlen = sizeof (int),
908 .mode = 0644,
909 .proc_handler = &proc_dointvec,
910 },
911 #endif
912 #ifdef CONFIG_RT_MUTEXES
913 {
914 .ctl_name = KERN_MAX_LOCK_DEPTH,
915 .procname = "max_lock_depth",
916 .data = &max_lock_depth,
917 .maxlen = sizeof(int),
918 .mode = 0644,
919 .proc_handler = &proc_dointvec,
920 },
921 #endif
922 {
923 .ctl_name = CTL_UNNUMBERED,
924 .procname = "poweroff_cmd",
925 .data = &poweroff_cmd,
926 .maxlen = POWEROFF_CMD_PATH_LEN,
927 .mode = 0644,
928 .proc_handler = &proc_dostring,
929 .strategy = &sysctl_string,
930 },
931 #ifdef CONFIG_KEYS
932 {
933 .ctl_name = CTL_UNNUMBERED,
934 .procname = "keys",
935 .mode = 0555,
936 .child = key_sysctls,
937 },
938 #endif
939 #ifdef CONFIG_RCU_TORTURE_TEST
940 {
941 .ctl_name = CTL_UNNUMBERED,
942 .procname = "rcutorture_runnable",
943 .data = &rcutorture_runnable,
944 .maxlen = sizeof(int),
945 .mode = 0644,
946 .proc_handler = &proc_dointvec,
947 },
948 #endif
949 #ifdef CONFIG_SLOW_WORK
950 {
951 .ctl_name = CTL_UNNUMBERED,
952 .procname = "slow-work",
953 .mode = 0555,
954 .child = slow_work_sysctls,
955 },
956 #endif
957 #ifdef CONFIG_PERF_COUNTERS
958 {
959 .ctl_name = CTL_UNNUMBERED,
960 .procname = "perf_counter_paranoid",
961 .data = &sysctl_perf_counter_paranoid,
962 .maxlen = sizeof(sysctl_perf_counter_paranoid),
963 .mode = 0644,
964 .proc_handler = &proc_dointvec,
965 },
966 {
967 .ctl_name = CTL_UNNUMBERED,
968 .procname = "perf_counter_mlock_kb",
969 .data = &sysctl_perf_counter_mlock,
970 .maxlen = sizeof(sysctl_perf_counter_mlock),
971 .mode = 0644,
972 .proc_handler = &proc_dointvec,
973 },
974 {
975 .ctl_name = CTL_UNNUMBERED,
976 .procname = "perf_counter_max_sample_rate",
977 .data = &sysctl_perf_counter_sample_rate,
978 .maxlen = sizeof(sysctl_perf_counter_sample_rate),
979 .mode = 0644,
980 .proc_handler = &proc_dointvec,
981 },
982 #endif
983 #ifdef CONFIG_KMEMCHECK
984 {
985 .ctl_name = CTL_UNNUMBERED,
986 .procname = "kmemcheck",
987 .data = &kmemcheck_enabled,
988 .maxlen = sizeof(int),
989 .mode = 0644,
990 .proc_handler = &proc_dointvec,
991 },
992 #endif
993
994 /*
995 * NOTE: do not add new entries to this table unless you have read
996 * Documentation/sysctl/ctl_unnumbered.txt
997 */
998 { .ctl_name = 0 }
999 };
1000
1001 static struct ctl_table vm_table[] = {
1002 {
1003 .ctl_name = VM_OVERCOMMIT_MEMORY,
1004 .procname = "overcommit_memory",
1005 .data = &sysctl_overcommit_memory,
1006 .maxlen = sizeof(sysctl_overcommit_memory),
1007 .mode = 0644,
1008 .proc_handler = &proc_dointvec,
1009 },
1010 {
1011 .ctl_name = VM_PANIC_ON_OOM,
1012 .procname = "panic_on_oom",
1013 .data = &sysctl_panic_on_oom,
1014 .maxlen = sizeof(sysctl_panic_on_oom),
1015 .mode = 0644,
1016 .proc_handler = &proc_dointvec,
1017 },
1018 {
1019 .ctl_name = CTL_UNNUMBERED,
1020 .procname = "oom_kill_allocating_task",
1021 .data = &sysctl_oom_kill_allocating_task,
1022 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1023 .mode = 0644,
1024 .proc_handler = &proc_dointvec,
1025 },
1026 {
1027 .ctl_name = CTL_UNNUMBERED,
1028 .procname = "oom_dump_tasks",
1029 .data = &sysctl_oom_dump_tasks,
1030 .maxlen = sizeof(sysctl_oom_dump_tasks),
1031 .mode = 0644,
1032 .proc_handler = &proc_dointvec,
1033 },
1034 {
1035 .ctl_name = VM_OVERCOMMIT_RATIO,
1036 .procname = "overcommit_ratio",
1037 .data = &sysctl_overcommit_ratio,
1038 .maxlen = sizeof(sysctl_overcommit_ratio),
1039 .mode = 0644,
1040 .proc_handler = &proc_dointvec,
1041 },
1042 {
1043 .ctl_name = VM_PAGE_CLUSTER,
1044 .procname = "page-cluster",
1045 .data = &page_cluster,
1046 .maxlen = sizeof(int),
1047 .mode = 0644,
1048 .proc_handler = &proc_dointvec,
1049 },
1050 {
1051 .ctl_name = VM_DIRTY_BACKGROUND,
1052 .procname = "dirty_background_ratio",
1053 .data = &dirty_background_ratio,
1054 .maxlen = sizeof(dirty_background_ratio),
1055 .mode = 0644,
1056 .proc_handler = &dirty_background_ratio_handler,
1057 .strategy = &sysctl_intvec,
1058 .extra1 = &zero,
1059 .extra2 = &one_hundred,
1060 },
1061 {
1062 .ctl_name = CTL_UNNUMBERED,
1063 .procname = "dirty_background_bytes",
1064 .data = &dirty_background_bytes,
1065 .maxlen = sizeof(dirty_background_bytes),
1066 .mode = 0644,
1067 .proc_handler = &dirty_background_bytes_handler,
1068 .strategy = &sysctl_intvec,
1069 .extra1 = &one_ul,
1070 },
1071 {
1072 .ctl_name = VM_DIRTY_RATIO,
1073 .procname = "dirty_ratio",
1074 .data = &vm_dirty_ratio,
1075 .maxlen = sizeof(vm_dirty_ratio),
1076 .mode = 0644,
1077 .proc_handler = &dirty_ratio_handler,
1078 .strategy = &sysctl_intvec,
1079 .extra1 = &zero,
1080 .extra2 = &one_hundred,
1081 },
1082 {
1083 .ctl_name = CTL_UNNUMBERED,
1084 .procname = "dirty_bytes",
1085 .data = &vm_dirty_bytes,
1086 .maxlen = sizeof(vm_dirty_bytes),
1087 .mode = 0644,
1088 .proc_handler = &dirty_bytes_handler,
1089 .strategy = &sysctl_intvec,
1090 .extra1 = &dirty_bytes_min,
1091 },
1092 {
1093 .procname = "dirty_writeback_centisecs",
1094 .data = &dirty_writeback_interval,
1095 .maxlen = sizeof(dirty_writeback_interval),
1096 .mode = 0644,
1097 .proc_handler = &dirty_writeback_centisecs_handler,
1098 },
1099 {
1100 .procname = "dirty_expire_centisecs",
1101 .data = &dirty_expire_interval,
1102 .maxlen = sizeof(dirty_expire_interval),
1103 .mode = 0644,
1104 .proc_handler = &proc_dointvec,
1105 },
1106 {
1107 .ctl_name = VM_NR_PDFLUSH_THREADS,
1108 .procname = "nr_pdflush_threads",
1109 .data = &nr_pdflush_threads,
1110 .maxlen = sizeof nr_pdflush_threads,
1111 .mode = 0444 /* read-only*/,
1112 .proc_handler = &proc_dointvec,
1113 },
1114 {
1115 .ctl_name = VM_SWAPPINESS,
1116 .procname = "swappiness",
1117 .data = &vm_swappiness,
1118 .maxlen = sizeof(vm_swappiness),
1119 .mode = 0644,
1120 .proc_handler = &proc_dointvec_minmax,
1121 .strategy = &sysctl_intvec,
1122 .extra1 = &zero,
1123 .extra2 = &one_hundred,
1124 },
1125 #ifdef CONFIG_HUGETLB_PAGE
1126 {
1127 .procname = "nr_hugepages",
1128 .data = NULL,
1129 .maxlen = sizeof(unsigned long),
1130 .mode = 0644,
1131 .proc_handler = &hugetlb_sysctl_handler,
1132 .extra1 = (void *)&hugetlb_zero,
1133 .extra2 = (void *)&hugetlb_infinity,
1134 },
1135 {
1136 .ctl_name = VM_HUGETLB_GROUP,
1137 .procname = "hugetlb_shm_group",
1138 .data = &sysctl_hugetlb_shm_group,
1139 .maxlen = sizeof(gid_t),
1140 .mode = 0644,
1141 .proc_handler = &proc_dointvec,
1142 },
1143 {
1144 .ctl_name = CTL_UNNUMBERED,
1145 .procname = "hugepages_treat_as_movable",
1146 .data = &hugepages_treat_as_movable,
1147 .maxlen = sizeof(int),
1148 .mode = 0644,
1149 .proc_handler = &hugetlb_treat_movable_handler,
1150 },
1151 {
1152 .ctl_name = CTL_UNNUMBERED,
1153 .procname = "nr_overcommit_hugepages",
1154 .data = NULL,
1155 .maxlen = sizeof(unsigned long),
1156 .mode = 0644,
1157 .proc_handler = &hugetlb_overcommit_handler,
1158 .extra1 = (void *)&hugetlb_zero,
1159 .extra2 = (void *)&hugetlb_infinity,
1160 },
1161 #endif
1162 {
1163 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
1164 .procname = "lowmem_reserve_ratio",
1165 .data = &sysctl_lowmem_reserve_ratio,
1166 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1167 .mode = 0644,
1168 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
1169 .strategy = &sysctl_intvec,
1170 },
1171 {
1172 .ctl_name = VM_DROP_PAGECACHE,
1173 .procname = "drop_caches",
1174 .data = &sysctl_drop_caches,
1175 .maxlen = sizeof(int),
1176 .mode = 0644,
1177 .proc_handler = drop_caches_sysctl_handler,
1178 .strategy = &sysctl_intvec,
1179 },
1180 {
1181 .ctl_name = VM_MIN_FREE_KBYTES,
1182 .procname = "min_free_kbytes",
1183 .data = &min_free_kbytes,
1184 .maxlen = sizeof(min_free_kbytes),
1185 .mode = 0644,
1186 .proc_handler = &min_free_kbytes_sysctl_handler,
1187 .strategy = &sysctl_intvec,
1188 .extra1 = &zero,
1189 },
1190 {
1191 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1192 .procname = "percpu_pagelist_fraction",
1193 .data = &percpu_pagelist_fraction,
1194 .maxlen = sizeof(percpu_pagelist_fraction),
1195 .mode = 0644,
1196 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1197 .strategy = &sysctl_intvec,
1198 .extra1 = &min_percpu_pagelist_fract,
1199 },
1200 #ifdef CONFIG_MMU
1201 {
1202 .ctl_name = VM_MAX_MAP_COUNT,
1203 .procname = "max_map_count",
1204 .data = &sysctl_max_map_count,
1205 .maxlen = sizeof(sysctl_max_map_count),
1206 .mode = 0644,
1207 .proc_handler = &proc_dointvec
1208 },
1209 #else
1210 {
1211 .ctl_name = CTL_UNNUMBERED,
1212 .procname = "nr_trim_pages",
1213 .data = &sysctl_nr_trim_pages,
1214 .maxlen = sizeof(sysctl_nr_trim_pages),
1215 .mode = 0644,
1216 .proc_handler = &proc_dointvec_minmax,
1217 .strategy = &sysctl_intvec,
1218 .extra1 = &zero,
1219 },
1220 #endif
1221 {
1222 .ctl_name = VM_LAPTOP_MODE,
1223 .procname = "laptop_mode",
1224 .data = &laptop_mode,
1225 .maxlen = sizeof(laptop_mode),
1226 .mode = 0644,
1227 .proc_handler = &proc_dointvec_jiffies,
1228 .strategy = &sysctl_jiffies,
1229 },
1230 {
1231 .ctl_name = VM_BLOCK_DUMP,
1232 .procname = "block_dump",
1233 .data = &block_dump,
1234 .maxlen = sizeof(block_dump),
1235 .mode = 0644,
1236 .proc_handler = &proc_dointvec,
1237 .strategy = &sysctl_intvec,
1238 .extra1 = &zero,
1239 },
1240 {
1241 .ctl_name = VM_VFS_CACHE_PRESSURE,
1242 .procname = "vfs_cache_pressure",
1243 .data = &sysctl_vfs_cache_pressure,
1244 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1245 .mode = 0644,
1246 .proc_handler = &proc_dointvec,
1247 .strategy = &sysctl_intvec,
1248 .extra1 = &zero,
1249 },
1250 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1251 {
1252 .ctl_name = VM_LEGACY_VA_LAYOUT,
1253 .procname = "legacy_va_layout",
1254 .data = &sysctl_legacy_va_layout,
1255 .maxlen = sizeof(sysctl_legacy_va_layout),
1256 .mode = 0644,
1257 .proc_handler = &proc_dointvec,
1258 .strategy = &sysctl_intvec,
1259 .extra1 = &zero,
1260 },
1261 #endif
1262 #ifdef CONFIG_NUMA
1263 {
1264 .ctl_name = VM_ZONE_RECLAIM_MODE,
1265 .procname = "zone_reclaim_mode",
1266 .data = &zone_reclaim_mode,
1267 .maxlen = sizeof(zone_reclaim_mode),
1268 .mode = 0644,
1269 .proc_handler = &proc_dointvec,
1270 .strategy = &sysctl_intvec,
1271 .extra1 = &zero,
1272 },
1273 {
1274 .ctl_name = VM_MIN_UNMAPPED,
1275 .procname = "min_unmapped_ratio",
1276 .data = &sysctl_min_unmapped_ratio,
1277 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1278 .mode = 0644,
1279 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1280 .strategy = &sysctl_intvec,
1281 .extra1 = &zero,
1282 .extra2 = &one_hundred,
1283 },
1284 {
1285 .ctl_name = VM_MIN_SLAB,
1286 .procname = "min_slab_ratio",
1287 .data = &sysctl_min_slab_ratio,
1288 .maxlen = sizeof(sysctl_min_slab_ratio),
1289 .mode = 0644,
1290 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1291 .strategy = &sysctl_intvec,
1292 .extra1 = &zero,
1293 .extra2 = &one_hundred,
1294 },
1295 #endif
1296 #ifdef CONFIG_SMP
1297 {
1298 .ctl_name = CTL_UNNUMBERED,
1299 .procname = "stat_interval",
1300 .data = &sysctl_stat_interval,
1301 .maxlen = sizeof(sysctl_stat_interval),
1302 .mode = 0644,
1303 .proc_handler = &proc_dointvec_jiffies,
1304 .strategy = &sysctl_jiffies,
1305 },
1306 #endif
1307 {
1308 .ctl_name = CTL_UNNUMBERED,
1309 .procname = "mmap_min_addr",
1310 .data = &dac_mmap_min_addr,
1311 .maxlen = sizeof(unsigned long),
1312 .mode = 0644,
1313 .proc_handler = &mmap_min_addr_handler,
1314 },
1315 #ifdef CONFIG_NUMA
1316 {
1317 .ctl_name = CTL_UNNUMBERED,
1318 .procname = "numa_zonelist_order",
1319 .data = &numa_zonelist_order,
1320 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1321 .mode = 0644,
1322 .proc_handler = &numa_zonelist_order_handler,
1323 .strategy = &sysctl_string,
1324 },
1325 #endif
1326 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1327 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1328 {
1329 .ctl_name = VM_VDSO_ENABLED,
1330 .procname = "vdso_enabled",
1331 .data = &vdso_enabled,
1332 .maxlen = sizeof(vdso_enabled),
1333 .mode = 0644,
1334 .proc_handler = &proc_dointvec,
1335 .strategy = &sysctl_intvec,
1336 .extra1 = &zero,
1337 },
1338 #endif
1339 #ifdef CONFIG_HIGHMEM
1340 {
1341 .ctl_name = CTL_UNNUMBERED,
1342 .procname = "highmem_is_dirtyable",
1343 .data = &vm_highmem_is_dirtyable,
1344 .maxlen = sizeof(vm_highmem_is_dirtyable),
1345 .mode = 0644,
1346 .proc_handler = &proc_dointvec_minmax,
1347 .strategy = &sysctl_intvec,
1348 .extra1 = &zero,
1349 .extra2 = &one,
1350 },
1351 #endif
1352 {
1353 .ctl_name = CTL_UNNUMBERED,
1354 .procname = "scan_unevictable_pages",
1355 .data = &scan_unevictable_pages,
1356 .maxlen = sizeof(scan_unevictable_pages),
1357 .mode = 0644,
1358 .proc_handler = &scan_unevictable_handler,
1359 },
1360 /*
1361 * NOTE: do not add new entries to this table unless you have read
1362 * Documentation/sysctl/ctl_unnumbered.txt
1363 */
1364 { .ctl_name = 0 }
1365 };
1366
1367 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1368 static struct ctl_table binfmt_misc_table[] = {
1369 { .ctl_name = 0 }
1370 };
1371 #endif
1372
1373 static struct ctl_table fs_table[] = {
1374 {
1375 .ctl_name = FS_NRINODE,
1376 .procname = "inode-nr",
1377 .data = &inodes_stat,
1378 .maxlen = 2*sizeof(int),
1379 .mode = 0444,
1380 .proc_handler = &proc_dointvec,
1381 },
1382 {
1383 .ctl_name = FS_STATINODE,
1384 .procname = "inode-state",
1385 .data = &inodes_stat,
1386 .maxlen = 7*sizeof(int),
1387 .mode = 0444,
1388 .proc_handler = &proc_dointvec,
1389 },
1390 {
1391 .procname = "file-nr",
1392 .data = &files_stat,
1393 .maxlen = 3*sizeof(int),
1394 .mode = 0444,
1395 .proc_handler = &proc_nr_files,
1396 },
1397 {
1398 .ctl_name = FS_MAXFILE,
1399 .procname = "file-max",
1400 .data = &files_stat.max_files,
1401 .maxlen = sizeof(int),
1402 .mode = 0644,
1403 .proc_handler = &proc_dointvec,
1404 },
1405 {
1406 .ctl_name = CTL_UNNUMBERED,
1407 .procname = "nr_open",
1408 .data = &sysctl_nr_open,
1409 .maxlen = sizeof(int),
1410 .mode = 0644,
1411 .proc_handler = &proc_dointvec_minmax,
1412 .extra1 = &sysctl_nr_open_min,
1413 .extra2 = &sysctl_nr_open_max,
1414 },
1415 {
1416 .ctl_name = FS_DENTRY,
1417 .procname = "dentry-state",
1418 .data = &dentry_stat,
1419 .maxlen = 6*sizeof(int),
1420 .mode = 0444,
1421 .proc_handler = &proc_dointvec,
1422 },
1423 {
1424 .ctl_name = FS_OVERFLOWUID,
1425 .procname = "overflowuid",
1426 .data = &fs_overflowuid,
1427 .maxlen = sizeof(int),
1428 .mode = 0644,
1429 .proc_handler = &proc_dointvec_minmax,
1430 .strategy = &sysctl_intvec,
1431 .extra1 = &minolduid,
1432 .extra2 = &maxolduid,
1433 },
1434 {
1435 .ctl_name = FS_OVERFLOWGID,
1436 .procname = "overflowgid",
1437 .data = &fs_overflowgid,
1438 .maxlen = sizeof(int),
1439 .mode = 0644,
1440 .proc_handler = &proc_dointvec_minmax,
1441 .strategy = &sysctl_intvec,
1442 .extra1 = &minolduid,
1443 .extra2 = &maxolduid,
1444 },
1445 #ifdef CONFIG_FILE_LOCKING
1446 {
1447 .ctl_name = FS_LEASES,
1448 .procname = "leases-enable",
1449 .data = &leases_enable,
1450 .maxlen = sizeof(int),
1451 .mode = 0644,
1452 .proc_handler = &proc_dointvec,
1453 },
1454 #endif
1455 #ifdef CONFIG_DNOTIFY
1456 {
1457 .ctl_name = FS_DIR_NOTIFY,
1458 .procname = "dir-notify-enable",
1459 .data = &dir_notify_enable,
1460 .maxlen = sizeof(int),
1461 .mode = 0644,
1462 .proc_handler = &proc_dointvec,
1463 },
1464 #endif
1465 #ifdef CONFIG_MMU
1466 #ifdef CONFIG_FILE_LOCKING
1467 {
1468 .ctl_name = FS_LEASE_TIME,
1469 .procname = "lease-break-time",
1470 .data = &lease_break_time,
1471 .maxlen = sizeof(int),
1472 .mode = 0644,
1473 .proc_handler = &proc_dointvec,
1474 },
1475 #endif
1476 #ifdef CONFIG_AIO
1477 {
1478 .procname = "aio-nr",
1479 .data = &aio_nr,
1480 .maxlen = sizeof(aio_nr),
1481 .mode = 0444,
1482 .proc_handler = &proc_doulongvec_minmax,
1483 },
1484 {
1485 .procname = "aio-max-nr",
1486 .data = &aio_max_nr,
1487 .maxlen = sizeof(aio_max_nr),
1488 .mode = 0644,
1489 .proc_handler = &proc_doulongvec_minmax,
1490 },
1491 #endif /* CONFIG_AIO */
1492 #ifdef CONFIG_INOTIFY_USER
1493 {
1494 .ctl_name = FS_INOTIFY,
1495 .procname = "inotify",
1496 .mode = 0555,
1497 .child = inotify_table,
1498 },
1499 #endif
1500 #ifdef CONFIG_EPOLL
1501 {
1502 .procname = "epoll",
1503 .mode = 0555,
1504 .child = epoll_table,
1505 },
1506 #endif
1507 #endif
1508 {
1509 .ctl_name = KERN_SETUID_DUMPABLE,
1510 .procname = "suid_dumpable",
1511 .data = &suid_dumpable,
1512 .maxlen = sizeof(int),
1513 .mode = 0644,
1514 .proc_handler = &proc_dointvec_minmax,
1515 .strategy = &sysctl_intvec,
1516 .extra1 = &zero,
1517 .extra2 = &two,
1518 },
1519 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1520 {
1521 .ctl_name = CTL_UNNUMBERED,
1522 .procname = "binfmt_misc",
1523 .mode = 0555,
1524 .child = binfmt_misc_table,
1525 },
1526 #endif
1527 /*
1528 * NOTE: do not add new entries to this table unless you have read
1529 * Documentation/sysctl/ctl_unnumbered.txt
1530 */
1531 { .ctl_name = 0 }
1532 };
1533
1534 static struct ctl_table debug_table[] = {
1535 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1536 {
1537 .ctl_name = CTL_UNNUMBERED,
1538 .procname = "exception-trace",
1539 .data = &show_unhandled_signals,
1540 .maxlen = sizeof(int),
1541 .mode = 0644,
1542 .proc_handler = proc_dointvec
1543 },
1544 #endif
1545 { .ctl_name = 0 }
1546 };
1547
1548 static struct ctl_table dev_table[] = {
1549 { .ctl_name = 0 }
1550 };
1551
1552 static DEFINE_SPINLOCK(sysctl_lock);
1553
1554 /* called under sysctl_lock */
1555 static int use_table(struct ctl_table_header *p)
1556 {
1557 if (unlikely(p->unregistering))
1558 return 0;
1559 p->used++;
1560 return 1;
1561 }
1562
1563 /* called under sysctl_lock */
1564 static void unuse_table(struct ctl_table_header *p)
1565 {
1566 if (!--p->used)
1567 if (unlikely(p->unregistering))
1568 complete(p->unregistering);
1569 }
1570
1571 /* called under sysctl_lock, will reacquire if has to wait */
1572 static void start_unregistering(struct ctl_table_header *p)
1573 {
1574 /*
1575 * if p->used is 0, nobody will ever touch that entry again;
1576 * we'll eliminate all paths to it before dropping sysctl_lock
1577 */
1578 if (unlikely(p->used)) {
1579 struct completion wait;
1580 init_completion(&wait);
1581 p->unregistering = &wait;
1582 spin_unlock(&sysctl_lock);
1583 wait_for_completion(&wait);
1584 spin_lock(&sysctl_lock);
1585 } else {
1586 /* anything non-NULL; we'll never dereference it */
1587 p->unregistering = ERR_PTR(-EINVAL);
1588 }
1589 /*
1590 * do not remove from the list until nobody holds it; walking the
1591 * list in do_sysctl() relies on that.
1592 */
1593 list_del_init(&p->ctl_entry);
1594 }
1595
1596 void sysctl_head_get(struct ctl_table_header *head)
1597 {
1598 spin_lock(&sysctl_lock);
1599 head->count++;
1600 spin_unlock(&sysctl_lock);
1601 }
1602
1603 void sysctl_head_put(struct ctl_table_header *head)
1604 {
1605 spin_lock(&sysctl_lock);
1606 if (!--head->count)
1607 kfree(head);
1608 spin_unlock(&sysctl_lock);
1609 }
1610
1611 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1612 {
1613 if (!head)
1614 BUG();
1615 spin_lock(&sysctl_lock);
1616 if (!use_table(head))
1617 head = ERR_PTR(-ENOENT);
1618 spin_unlock(&sysctl_lock);
1619 return head;
1620 }
1621
1622 void sysctl_head_finish(struct ctl_table_header *head)
1623 {
1624 if (!head)
1625 return;
1626 spin_lock(&sysctl_lock);
1627 unuse_table(head);
1628 spin_unlock(&sysctl_lock);
1629 }
1630
1631 static struct ctl_table_set *
1632 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1633 {
1634 struct ctl_table_set *set = &root->default_set;
1635 if (root->lookup)
1636 set = root->lookup(root, namespaces);
1637 return set;
1638 }
1639
1640 static struct list_head *
1641 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1642 {
1643 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1644 return &set->list;
1645 }
1646
1647 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1648 struct ctl_table_header *prev)
1649 {
1650 struct ctl_table_root *root;
1651 struct list_head *header_list;
1652 struct ctl_table_header *head;
1653 struct list_head *tmp;
1654
1655 spin_lock(&sysctl_lock);
1656 if (prev) {
1657 head = prev;
1658 tmp = &prev->ctl_entry;
1659 unuse_table(prev);
1660 goto next;
1661 }
1662 tmp = &root_table_header.ctl_entry;
1663 for (;;) {
1664 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1665
1666 if (!use_table(head))
1667 goto next;
1668 spin_unlock(&sysctl_lock);
1669 return head;
1670 next:
1671 root = head->root;
1672 tmp = tmp->next;
1673 header_list = lookup_header_list(root, namespaces);
1674 if (tmp != header_list)
1675 continue;
1676
1677 do {
1678 root = list_entry(root->root_list.next,
1679 struct ctl_table_root, root_list);
1680 if (root == &sysctl_table_root)
1681 goto out;
1682 header_list = lookup_header_list(root, namespaces);
1683 } while (list_empty(header_list));
1684 tmp = header_list->next;
1685 }
1686 out:
1687 spin_unlock(&sysctl_lock);
1688 return NULL;
1689 }
1690
1691 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1692 {
1693 return __sysctl_head_next(current->nsproxy, prev);
1694 }
1695
1696 void register_sysctl_root(struct ctl_table_root *root)
1697 {
1698 spin_lock(&sysctl_lock);
1699 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1700 spin_unlock(&sysctl_lock);
1701 }
1702
1703 #ifdef CONFIG_SYSCTL_SYSCALL
1704 /* Perform the actual read/write of a sysctl table entry. */
1705 static int do_sysctl_strategy(struct ctl_table_root *root,
1706 struct ctl_table *table,
1707 void __user *oldval, size_t __user *oldlenp,
1708 void __user *newval, size_t newlen)
1709 {
1710 int op = 0, rc;
1711
1712 if (oldval)
1713 op |= MAY_READ;
1714 if (newval)
1715 op |= MAY_WRITE;
1716 if (sysctl_perm(root, table, op))
1717 return -EPERM;
1718
1719 if (table->strategy) {
1720 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1721 if (rc < 0)
1722 return rc;
1723 if (rc > 0)
1724 return 0;
1725 }
1726
1727 /* If there is no strategy routine, or if the strategy returns
1728 * zero, proceed with automatic r/w */
1729 if (table->data && table->maxlen) {
1730 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1731 if (rc < 0)
1732 return rc;
1733 }
1734 return 0;
1735 }
1736
1737 static int parse_table(int __user *name, int nlen,
1738 void __user *oldval, size_t __user *oldlenp,
1739 void __user *newval, size_t newlen,
1740 struct ctl_table_root *root,
1741 struct ctl_table *table)
1742 {
1743 int n;
1744 repeat:
1745 if (!nlen)
1746 return -ENOTDIR;
1747 if (get_user(n, name))
1748 return -EFAULT;
1749 for ( ; table->ctl_name || table->procname; table++) {
1750 if (!table->ctl_name)
1751 continue;
1752 if (n == table->ctl_name) {
1753 int error;
1754 if (table->child) {
1755 if (sysctl_perm(root, table, MAY_EXEC))
1756 return -EPERM;
1757 name++;
1758 nlen--;
1759 table = table->child;
1760 goto repeat;
1761 }
1762 error = do_sysctl_strategy(root, table,
1763 oldval, oldlenp,
1764 newval, newlen);
1765 return error;
1766 }
1767 }
1768 return -ENOTDIR;
1769 }
1770
1771 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1772 void __user *newval, size_t newlen)
1773 {
1774 struct ctl_table_header *head;
1775 int error = -ENOTDIR;
1776
1777 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1778 return -ENOTDIR;
1779 if (oldval) {
1780 int old_len;
1781 if (!oldlenp || get_user(old_len, oldlenp))
1782 return -EFAULT;
1783 }
1784
1785 for (head = sysctl_head_next(NULL); head;
1786 head = sysctl_head_next(head)) {
1787 error = parse_table(name, nlen, oldval, oldlenp,
1788 newval, newlen,
1789 head->root, head->ctl_table);
1790 if (error != -ENOTDIR) {
1791 sysctl_head_finish(head);
1792 break;
1793 }
1794 }
1795 return error;
1796 }
1797
1798 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1799 {
1800 struct __sysctl_args tmp;
1801 int error;
1802
1803 if (copy_from_user(&tmp, args, sizeof(tmp)))
1804 return -EFAULT;
1805
1806 error = deprecated_sysctl_warning(&tmp);
1807 if (error)
1808 goto out;
1809
1810 lock_kernel();
1811 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1812 tmp.newval, tmp.newlen);
1813 unlock_kernel();
1814 out:
1815 return error;
1816 }
1817 #endif /* CONFIG_SYSCTL_SYSCALL */
1818
1819 /*
1820 * sysctl_perm does NOT grant the superuser all rights automatically, because
1821 * some sysctl variables are readonly even to root.
1822 */
1823
1824 static int test_perm(int mode, int op)
1825 {
1826 if (!current_euid())
1827 mode >>= 6;
1828 else if (in_egroup_p(0))
1829 mode >>= 3;
1830 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1831 return 0;
1832 return -EACCES;
1833 }
1834
1835 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1836 {
1837 int error;
1838 int mode;
1839
1840 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1841 if (error)
1842 return error;
1843
1844 if (root->permissions)
1845 mode = root->permissions(root, current->nsproxy, table);
1846 else
1847 mode = table->mode;
1848
1849 return test_perm(mode, op);
1850 }
1851
1852 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1853 {
1854 for (; table->ctl_name || table->procname; table++) {
1855 table->parent = parent;
1856 if (table->child)
1857 sysctl_set_parent(table, table->child);
1858 }
1859 }
1860
1861 static __init int sysctl_init(void)
1862 {
1863 sysctl_set_parent(NULL, root_table);
1864 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1865 {
1866 int err;
1867 err = sysctl_check_table(current->nsproxy, root_table);
1868 }
1869 #endif
1870 return 0;
1871 }
1872
1873 core_initcall(sysctl_init);
1874
1875 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1876 struct ctl_table *table)
1877 {
1878 struct ctl_table *p;
1879 const char *s = branch->procname;
1880
1881 /* branch should have named subdirectory as its first element */
1882 if (!s || !branch->child)
1883 return NULL;
1884
1885 /* ... and nothing else */
1886 if (branch[1].procname || branch[1].ctl_name)
1887 return NULL;
1888
1889 /* table should contain subdirectory with the same name */
1890 for (p = table; p->procname || p->ctl_name; p++) {
1891 if (!p->child)
1892 continue;
1893 if (p->procname && strcmp(p->procname, s) == 0)
1894 return p;
1895 }
1896 return NULL;
1897 }
1898
1899 /* see if attaching q to p would be an improvement */
1900 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1901 {
1902 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1903 struct ctl_table *next;
1904 int is_better = 0;
1905 int not_in_parent = !p->attached_by;
1906
1907 while ((next = is_branch_in(by, to)) != NULL) {
1908 if (by == q->attached_by)
1909 is_better = 1;
1910 if (to == p->attached_by)
1911 not_in_parent = 1;
1912 by = by->child;
1913 to = next->child;
1914 }
1915
1916 if (is_better && not_in_parent) {
1917 q->attached_by = by;
1918 q->attached_to = to;
1919 q->parent = p;
1920 }
1921 }
1922
1923 /**
1924 * __register_sysctl_paths - register a sysctl hierarchy
1925 * @root: List of sysctl headers to register on
1926 * @namespaces: Data to compute which lists of sysctl entries are visible
1927 * @path: The path to the directory the sysctl table is in.
1928 * @table: the top-level table structure
1929 *
1930 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1931 * array. A completely 0 filled entry terminates the table.
1932 *
1933 * The members of the &struct ctl_table structure are used as follows:
1934 *
1935 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1936 * must be unique within that level of sysctl
1937 *
1938 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1939 * enter a sysctl file
1940 *
1941 * data - a pointer to data for use by proc_handler
1942 *
1943 * maxlen - the maximum size in bytes of the data
1944 *
1945 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1946 *
1947 * child - a pointer to the child sysctl table if this entry is a directory, or
1948 * %NULL.
1949 *
1950 * proc_handler - the text handler routine (described below)
1951 *
1952 * strategy - the strategy routine (described below)
1953 *
1954 * de - for internal use by the sysctl routines
1955 *
1956 * extra1, extra2 - extra pointers usable by the proc handler routines
1957 *
1958 * Leaf nodes in the sysctl tree will be represented by a single file
1959 * under /proc; non-leaf nodes will be represented by directories.
1960 *
1961 * sysctl(2) can automatically manage read and write requests through
1962 * the sysctl table. The data and maxlen fields of the ctl_table
1963 * struct enable minimal validation of the values being written to be
1964 * performed, and the mode field allows minimal authentication.
1965 *
1966 * More sophisticated management can be enabled by the provision of a
1967 * strategy routine with the table entry. This will be called before
1968 * any automatic read or write of the data is performed.
1969 *
1970 * The strategy routine may return
1971 *
1972 * < 0 - Error occurred (error is passed to user process)
1973 *
1974 * 0 - OK - proceed with automatic read or write.
1975 *
1976 * > 0 - OK - read or write has been done by the strategy routine, so
1977 * return immediately.
1978 *
1979 * There must be a proc_handler routine for any terminal nodes
1980 * mirrored under /proc/sys (non-terminals are handled by a built-in
1981 * directory handler). Several default handlers are available to
1982 * cover common cases -
1983 *
1984 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1985 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1986 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1987 *
1988 * It is the handler's job to read the input buffer from user memory
1989 * and process it. The handler should return 0 on success.
1990 *
1991 * This routine returns %NULL on a failure to register, and a pointer
1992 * to the table header on success.
1993 */
1994 struct ctl_table_header *__register_sysctl_paths(
1995 struct ctl_table_root *root,
1996 struct nsproxy *namespaces,
1997 const struct ctl_path *path, struct ctl_table *table)
1998 {
1999 struct ctl_table_header *header;
2000 struct ctl_table *new, **prevp;
2001 unsigned int n, npath;
2002 struct ctl_table_set *set;
2003
2004 /* Count the path components */
2005 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
2006 ;
2007
2008 /*
2009 * For each path component, allocate a 2-element ctl_table array.
2010 * The first array element will be filled with the sysctl entry
2011 * for this, the second will be the sentinel (ctl_name == 0).
2012 *
2013 * We allocate everything in one go so that we don't have to
2014 * worry about freeing additional memory in unregister_sysctl_table.
2015 */
2016 header = kzalloc(sizeof(struct ctl_table_header) +
2017 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2018 if (!header)
2019 return NULL;
2020
2021 new = (struct ctl_table *) (header + 1);
2022
2023 /* Now connect the dots */
2024 prevp = &header->ctl_table;
2025 for (n = 0; n < npath; ++n, ++path) {
2026 /* Copy the procname */
2027 new->procname = path->procname;
2028 new->ctl_name = path->ctl_name;
2029 new->mode = 0555;
2030
2031 *prevp = new;
2032 prevp = &new->child;
2033
2034 new += 2;
2035 }
2036 *prevp = table;
2037 header->ctl_table_arg = table;
2038
2039 INIT_LIST_HEAD(&header->ctl_entry);
2040 header->used = 0;
2041 header->unregistering = NULL;
2042 header->root = root;
2043 sysctl_set_parent(NULL, header->ctl_table);
2044 header->count = 1;
2045 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2046 if (sysctl_check_table(namespaces, header->ctl_table)) {
2047 kfree(header);
2048 return NULL;
2049 }
2050 #endif
2051 spin_lock(&sysctl_lock);
2052 header->set = lookup_header_set(root, namespaces);
2053 header->attached_by = header->ctl_table;
2054 header->attached_to = root_table;
2055 header->parent = &root_table_header;
2056 for (set = header->set; set; set = set->parent) {
2057 struct ctl_table_header *p;
2058 list_for_each_entry(p, &set->list, ctl_entry) {
2059 if (p->unregistering)
2060 continue;
2061 try_attach(p, header);
2062 }
2063 }
2064 header->parent->count++;
2065 list_add_tail(&header->ctl_entry, &header->set->list);
2066 spin_unlock(&sysctl_lock);
2067
2068 return header;
2069 }
2070
2071 /**
2072 * register_sysctl_table_path - register a sysctl table hierarchy
2073 * @path: The path to the directory the sysctl table is in.
2074 * @table: the top-level table structure
2075 *
2076 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2077 * array. A completely 0 filled entry terminates the table.
2078 *
2079 * See __register_sysctl_paths for more details.
2080 */
2081 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2082 struct ctl_table *table)
2083 {
2084 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2085 path, table);
2086 }
2087
2088 /**
2089 * register_sysctl_table - register a sysctl table hierarchy
2090 * @table: the top-level table structure
2091 *
2092 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2093 * array. A completely 0 filled entry terminates the table.
2094 *
2095 * See register_sysctl_paths for more details.
2096 */
2097 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2098 {
2099 static const struct ctl_path null_path[] = { {} };
2100
2101 return register_sysctl_paths(null_path, table);
2102 }
2103
2104 /**
2105 * unregister_sysctl_table - unregister a sysctl table hierarchy
2106 * @header: the header returned from register_sysctl_table
2107 *
2108 * Unregisters the sysctl table and all children. proc entries may not
2109 * actually be removed until they are no longer used by anyone.
2110 */
2111 void unregister_sysctl_table(struct ctl_table_header * header)
2112 {
2113 might_sleep();
2114
2115 if (header == NULL)
2116 return;
2117
2118 spin_lock(&sysctl_lock);
2119 start_unregistering(header);
2120 if (!--header->parent->count) {
2121 WARN_ON(1);
2122 kfree(header->parent);
2123 }
2124 if (!--header->count)
2125 kfree(header);
2126 spin_unlock(&sysctl_lock);
2127 }
2128
2129 int sysctl_is_seen(struct ctl_table_header *p)
2130 {
2131 struct ctl_table_set *set = p->set;
2132 int res;
2133 spin_lock(&sysctl_lock);
2134 if (p->unregistering)
2135 res = 0;
2136 else if (!set->is_seen)
2137 res = 1;
2138 else
2139 res = set->is_seen(set);
2140 spin_unlock(&sysctl_lock);
2141 return res;
2142 }
2143
2144 void setup_sysctl_set(struct ctl_table_set *p,
2145 struct ctl_table_set *parent,
2146 int (*is_seen)(struct ctl_table_set *))
2147 {
2148 INIT_LIST_HEAD(&p->list);
2149 p->parent = parent ? parent : &sysctl_table_root.default_set;
2150 p->is_seen = is_seen;
2151 }
2152
2153 #else /* !CONFIG_SYSCTL */
2154 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2155 {
2156 return NULL;
2157 }
2158
2159 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2160 struct ctl_table *table)
2161 {
2162 return NULL;
2163 }
2164
2165 void unregister_sysctl_table(struct ctl_table_header * table)
2166 {
2167 }
2168
2169 void setup_sysctl_set(struct ctl_table_set *p,
2170 struct ctl_table_set *parent,
2171 int (*is_seen)(struct ctl_table_set *))
2172 {
2173 }
2174
2175 void sysctl_head_put(struct ctl_table_header *head)
2176 {
2177 }
2178
2179 #endif /* CONFIG_SYSCTL */
2180
2181 /*
2182 * /proc/sys support
2183 */
2184
2185 #ifdef CONFIG_PROC_SYSCTL
2186
2187 static int _proc_do_string(void* data, int maxlen, int write,
2188 struct file *filp, void __user *buffer,
2189 size_t *lenp, loff_t *ppos)
2190 {
2191 size_t len;
2192 char __user *p;
2193 char c;
2194
2195 if (!data || !maxlen || !*lenp) {
2196 *lenp = 0;
2197 return 0;
2198 }
2199
2200 if (write) {
2201 len = 0;
2202 p = buffer;
2203 while (len < *lenp) {
2204 if (get_user(c, p++))
2205 return -EFAULT;
2206 if (c == 0 || c == '\n')
2207 break;
2208 len++;
2209 }
2210 if (len >= maxlen)
2211 len = maxlen-1;
2212 if(copy_from_user(data, buffer, len))
2213 return -EFAULT;
2214 ((char *) data)[len] = 0;
2215 *ppos += *lenp;
2216 } else {
2217 len = strlen(data);
2218 if (len > maxlen)
2219 len = maxlen;
2220
2221 if (*ppos > len) {
2222 *lenp = 0;
2223 return 0;
2224 }
2225
2226 data += *ppos;
2227 len -= *ppos;
2228
2229 if (len > *lenp)
2230 len = *lenp;
2231 if (len)
2232 if(copy_to_user(buffer, data, len))
2233 return -EFAULT;
2234 if (len < *lenp) {
2235 if(put_user('\n', ((char __user *) buffer) + len))
2236 return -EFAULT;
2237 len++;
2238 }
2239 *lenp = len;
2240 *ppos += len;
2241 }
2242 return 0;
2243 }
2244
2245 /**
2246 * proc_dostring - read a string sysctl
2247 * @table: the sysctl table
2248 * @write: %TRUE if this is a write to the sysctl file
2249 * @filp: the file structure
2250 * @buffer: the user buffer
2251 * @lenp: the size of the user buffer
2252 * @ppos: file position
2253 *
2254 * Reads/writes a string from/to the user buffer. If the kernel
2255 * buffer provided is not large enough to hold the string, the
2256 * string is truncated. The copied string is %NULL-terminated.
2257 * If the string is being read by the user process, it is copied
2258 * and a newline '\n' is added. It is truncated if the buffer is
2259 * not large enough.
2260 *
2261 * Returns 0 on success.
2262 */
2263 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2264 void __user *buffer, size_t *lenp, loff_t *ppos)
2265 {
2266 return _proc_do_string(table->data, table->maxlen, write, filp,
2267 buffer, lenp, ppos);
2268 }
2269
2270
2271 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2272 int *valp,
2273 int write, void *data)
2274 {
2275 if (write) {
2276 *valp = *negp ? -*lvalp : *lvalp;
2277 } else {
2278 int val = *valp;
2279 if (val < 0) {
2280 *negp = -1;
2281 *lvalp = (unsigned long)-val;
2282 } else {
2283 *negp = 0;
2284 *lvalp = (unsigned long)val;
2285 }
2286 }
2287 return 0;
2288 }
2289
2290 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2291 int write, struct file *filp, void __user *buffer,
2292 size_t *lenp, loff_t *ppos,
2293 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2294 int write, void *data),
2295 void *data)
2296 {
2297 #define TMPBUFLEN 21
2298 int *i, vleft, first = 1, neg;
2299 unsigned long lval;
2300 size_t left, len;
2301
2302 char buf[TMPBUFLEN], *p;
2303 char __user *s = buffer;
2304
2305 if (!tbl_data || !table->maxlen || !*lenp ||
2306 (*ppos && !write)) {
2307 *lenp = 0;
2308 return 0;
2309 }
2310
2311 i = (int *) tbl_data;
2312 vleft = table->maxlen / sizeof(*i);
2313 left = *lenp;
2314
2315 if (!conv)
2316 conv = do_proc_dointvec_conv;
2317
2318 for (; left && vleft--; i++, first=0) {
2319 if (write) {
2320 while (left) {
2321 char c;
2322 if (get_user(c, s))
2323 return -EFAULT;
2324 if (!isspace(c))
2325 break;
2326 left--;
2327 s++;
2328 }
2329 if (!left)
2330 break;
2331 neg = 0;
2332 len = left;
2333 if (len > sizeof(buf) - 1)
2334 len = sizeof(buf) - 1;
2335 if (copy_from_user(buf, s, len))
2336 return -EFAULT;
2337 buf[len] = 0;
2338 p = buf;
2339 if (*p == '-' && left > 1) {
2340 neg = 1;
2341 p++;
2342 }
2343 if (*p < '0' || *p > '9')
2344 break;
2345
2346 lval = simple_strtoul(p, &p, 0);
2347
2348 len = p-buf;
2349 if ((len < left) && *p && !isspace(*p))
2350 break;
2351 s += len;
2352 left -= len;
2353
2354 if (conv(&neg, &lval, i, 1, data))
2355 break;
2356 } else {
2357 p = buf;
2358 if (!first)
2359 *p++ = '\t';
2360
2361 if (conv(&neg, &lval, i, 0, data))
2362 break;
2363
2364 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2365 len = strlen(buf);
2366 if (len > left)
2367 len = left;
2368 if(copy_to_user(s, buf, len))
2369 return -EFAULT;
2370 left -= len;
2371 s += len;
2372 }
2373 }
2374
2375 if (!write && !first && left) {
2376 if(put_user('\n', s))
2377 return -EFAULT;
2378 left--, s++;
2379 }
2380 if (write) {
2381 while (left) {
2382 char c;
2383 if (get_user(c, s++))
2384 return -EFAULT;
2385 if (!isspace(c))
2386 break;
2387 left--;
2388 }
2389 }
2390 if (write && first)
2391 return -EINVAL;
2392 *lenp -= left;
2393 *ppos += *lenp;
2394 return 0;
2395 #undef TMPBUFLEN
2396 }
2397
2398 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2399 void __user *buffer, size_t *lenp, loff_t *ppos,
2400 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2401 int write, void *data),
2402 void *data)
2403 {
2404 return __do_proc_dointvec(table->data, table, write, filp,
2405 buffer, lenp, ppos, conv, data);
2406 }
2407
2408 /**
2409 * proc_dointvec - read a vector of integers
2410 * @table: the sysctl table
2411 * @write: %TRUE if this is a write to the sysctl file
2412 * @filp: the file structure
2413 * @buffer: the user buffer
2414 * @lenp: the size of the user buffer
2415 * @ppos: file position
2416 *
2417 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2418 * values from/to the user buffer, treated as an ASCII string.
2419 *
2420 * Returns 0 on success.
2421 */
2422 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2423 void __user *buffer, size_t *lenp, loff_t *ppos)
2424 {
2425 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2426 NULL,NULL);
2427 }
2428
2429 /*
2430 * Taint values can only be increased
2431 * This means we can safely use a temporary.
2432 */
2433 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2434 void __user *buffer, size_t *lenp, loff_t *ppos)
2435 {
2436 struct ctl_table t;
2437 unsigned long tmptaint = get_taint();
2438 int err;
2439
2440 if (write && !capable(CAP_SYS_ADMIN))
2441 return -EPERM;
2442
2443 t = *table;
2444 t.data = &tmptaint;
2445 err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2446 if (err < 0)
2447 return err;
2448
2449 if (write) {
2450 /*
2451 * Poor man's atomic or. Not worth adding a primitive
2452 * to everyone's atomic.h for this
2453 */
2454 int i;
2455 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2456 if ((tmptaint >> i) & 1)
2457 add_taint(i);
2458 }
2459 }
2460
2461 return err;
2462 }
2463
2464 struct do_proc_dointvec_minmax_conv_param {
2465 int *min;
2466 int *max;
2467 };
2468
2469 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2470 int *valp,
2471 int write, void *data)
2472 {
2473 struct do_proc_dointvec_minmax_conv_param *param = data;
2474 if (write) {
2475 int val = *negp ? -*lvalp : *lvalp;
2476 if ((param->min && *param->min > val) ||
2477 (param->max && *param->max < val))
2478 return -EINVAL;
2479 *valp = val;
2480 } else {
2481 int val = *valp;
2482 if (val < 0) {
2483 *negp = -1;
2484 *lvalp = (unsigned long)-val;
2485 } else {
2486 *negp = 0;
2487 *lvalp = (unsigned long)val;
2488 }
2489 }
2490 return 0;
2491 }
2492
2493 /**
2494 * proc_dointvec_minmax - read a vector of integers with min/max values
2495 * @table: the sysctl table
2496 * @write: %TRUE if this is a write to the sysctl file
2497 * @filp: the file structure
2498 * @buffer: the user buffer
2499 * @lenp: the size of the user buffer
2500 * @ppos: file position
2501 *
2502 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2503 * values from/to the user buffer, treated as an ASCII string.
2504 *
2505 * This routine will ensure the values are within the range specified by
2506 * table->extra1 (min) and table->extra2 (max).
2507 *
2508 * Returns 0 on success.
2509 */
2510 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2511 void __user *buffer, size_t *lenp, loff_t *ppos)
2512 {
2513 struct do_proc_dointvec_minmax_conv_param param = {
2514 .min = (int *) table->extra1,
2515 .max = (int *) table->extra2,
2516 };
2517 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2518 do_proc_dointvec_minmax_conv, &param);
2519 }
2520
2521 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2522 struct file *filp,
2523 void __user *buffer,
2524 size_t *lenp, loff_t *ppos,
2525 unsigned long convmul,
2526 unsigned long convdiv)
2527 {
2528 #define TMPBUFLEN 21
2529 unsigned long *i, *min, *max, val;
2530 int vleft, first=1, neg;
2531 size_t len, left;
2532 char buf[TMPBUFLEN], *p;
2533 char __user *s = buffer;
2534
2535 if (!data || !table->maxlen || !*lenp ||
2536 (*ppos && !write)) {
2537 *lenp = 0;
2538 return 0;
2539 }
2540
2541 i = (unsigned long *) data;
2542 min = (unsigned long *) table->extra1;
2543 max = (unsigned long *) table->extra2;
2544 vleft = table->maxlen / sizeof(unsigned long);
2545 left = *lenp;
2546
2547 for (; left && vleft--; i++, min++, max++, first=0) {
2548 if (write) {
2549 while (left) {
2550 char c;
2551 if (get_user(c, s))
2552 return -EFAULT;
2553 if (!isspace(c))
2554 break;
2555 left--;
2556 s++;
2557 }
2558 if (!left)
2559 break;
2560 neg = 0;
2561 len = left;
2562 if (len > TMPBUFLEN-1)
2563 len = TMPBUFLEN-1;
2564 if (copy_from_user(buf, s, len))
2565 return -EFAULT;
2566 buf[len] = 0;
2567 p = buf;
2568 if (*p == '-' && left > 1) {
2569 neg = 1;
2570 p++;
2571 }
2572 if (*p < '0' || *p > '9')
2573 break;
2574 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2575 len = p-buf;
2576 if ((len < left) && *p && !isspace(*p))
2577 break;
2578 if (neg)
2579 val = -val;
2580 s += len;
2581 left -= len;
2582
2583 if(neg)
2584 continue;
2585 if ((min && val < *min) || (max && val > *max))
2586 continue;
2587 *i = val;
2588 } else {
2589 p = buf;
2590 if (!first)
2591 *p++ = '\t';
2592 sprintf(p, "%lu", convdiv * (*i) / convmul);
2593 len = strlen(buf);
2594 if (len > left)
2595 len = left;
2596 if(copy_to_user(s, buf, len))
2597 return -EFAULT;
2598 left -= len;
2599 s += len;
2600 }
2601 }
2602
2603 if (!write && !first && left) {
2604 if(put_user('\n', s))
2605 return -EFAULT;
2606 left--, s++;
2607 }
2608 if (write) {
2609 while (left) {
2610 char c;
2611 if (get_user(c, s++))
2612 return -EFAULT;
2613 if (!isspace(c))
2614 break;
2615 left--;
2616 }
2617 }
2618 if (write && first)
2619 return -EINVAL;
2620 *lenp -= left;
2621 *ppos += *lenp;
2622 return 0;
2623 #undef TMPBUFLEN
2624 }
2625
2626 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2627 struct file *filp,
2628 void __user *buffer,
2629 size_t *lenp, loff_t *ppos,
2630 unsigned long convmul,
2631 unsigned long convdiv)
2632 {
2633 return __do_proc_doulongvec_minmax(table->data, table, write,
2634 filp, buffer, lenp, ppos, convmul, convdiv);
2635 }
2636
2637 /**
2638 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2639 * @table: the sysctl table
2640 * @write: %TRUE if this is a write to the sysctl file
2641 * @filp: the file structure
2642 * @buffer: the user buffer
2643 * @lenp: the size of the user buffer
2644 * @ppos: file position
2645 *
2646 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2647 * values from/to the user buffer, treated as an ASCII string.
2648 *
2649 * This routine will ensure the values are within the range specified by
2650 * table->extra1 (min) and table->extra2 (max).
2651 *
2652 * Returns 0 on success.
2653 */
2654 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2655 void __user *buffer, size_t *lenp, loff_t *ppos)
2656 {
2657 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2658 }
2659
2660 /**
2661 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2662 * @table: the sysctl table
2663 * @write: %TRUE if this is a write to the sysctl file
2664 * @filp: the file structure
2665 * @buffer: the user buffer
2666 * @lenp: the size of the user buffer
2667 * @ppos: file position
2668 *
2669 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2670 * values from/to the user buffer, treated as an ASCII string. The values
2671 * are treated as milliseconds, and converted to jiffies when they are stored.
2672 *
2673 * This routine will ensure the values are within the range specified by
2674 * table->extra1 (min) and table->extra2 (max).
2675 *
2676 * Returns 0 on success.
2677 */
2678 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2679 struct file *filp,
2680 void __user *buffer,
2681 size_t *lenp, loff_t *ppos)
2682 {
2683 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2684 lenp, ppos, HZ, 1000l);
2685 }
2686
2687
2688 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2689 int *valp,
2690 int write, void *data)
2691 {
2692 if (write) {
2693 if (*lvalp > LONG_MAX / HZ)
2694 return 1;
2695 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2696 } else {
2697 int val = *valp;
2698 unsigned long lval;
2699 if (val < 0) {
2700 *negp = -1;
2701 lval = (unsigned long)-val;
2702 } else {
2703 *negp = 0;
2704 lval = (unsigned long)val;
2705 }
2706 *lvalp = lval / HZ;
2707 }
2708 return 0;
2709 }
2710
2711 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2712 int *valp,
2713 int write, void *data)
2714 {
2715 if (write) {
2716 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2717 return 1;
2718 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2719 } else {
2720 int val = *valp;
2721 unsigned long lval;
2722 if (val < 0) {
2723 *negp = -1;
2724 lval = (unsigned long)-val;
2725 } else {
2726 *negp = 0;
2727 lval = (unsigned long)val;
2728 }
2729 *lvalp = jiffies_to_clock_t(lval);
2730 }
2731 return 0;
2732 }
2733
2734 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2735 int *valp,
2736 int write, void *data)
2737 {
2738 if (write) {
2739 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2740 } else {
2741 int val = *valp;
2742 unsigned long lval;
2743 if (val < 0) {
2744 *negp = -1;
2745 lval = (unsigned long)-val;
2746 } else {
2747 *negp = 0;
2748 lval = (unsigned long)val;
2749 }
2750 *lvalp = jiffies_to_msecs(lval);
2751 }
2752 return 0;
2753 }
2754
2755 /**
2756 * proc_dointvec_jiffies - read a vector of integers as seconds
2757 * @table: the sysctl table
2758 * @write: %TRUE if this is a write to the sysctl file
2759 * @filp: the file structure
2760 * @buffer: the user buffer
2761 * @lenp: the size of the user buffer
2762 * @ppos: file position
2763 *
2764 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2765 * values from/to the user buffer, treated as an ASCII string.
2766 * The values read are assumed to be in seconds, and are converted into
2767 * jiffies.
2768 *
2769 * Returns 0 on success.
2770 */
2771 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2772 void __user *buffer, size_t *lenp, loff_t *ppos)
2773 {
2774 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2775 do_proc_dointvec_jiffies_conv,NULL);
2776 }
2777
2778 /**
2779 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2780 * @table: the sysctl table
2781 * @write: %TRUE if this is a write to the sysctl file
2782 * @filp: the file structure
2783 * @buffer: the user buffer
2784 * @lenp: the size of the user buffer
2785 * @ppos: pointer to the file position
2786 *
2787 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2788 * values from/to the user buffer, treated as an ASCII string.
2789 * The values read are assumed to be in 1/USER_HZ seconds, and
2790 * are converted into jiffies.
2791 *
2792 * Returns 0 on success.
2793 */
2794 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2795 void __user *buffer, size_t *lenp, loff_t *ppos)
2796 {
2797 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2798 do_proc_dointvec_userhz_jiffies_conv,NULL);
2799 }
2800
2801 /**
2802 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2803 * @table: the sysctl table
2804 * @write: %TRUE if this is a write to the sysctl file
2805 * @filp: the file structure
2806 * @buffer: the user buffer
2807 * @lenp: the size of the user buffer
2808 * @ppos: file position
2809 * @ppos: the current position in the file
2810 *
2811 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2812 * values from/to the user buffer, treated as an ASCII string.
2813 * The values read are assumed to be in 1/1000 seconds, and
2814 * are converted into jiffies.
2815 *
2816 * Returns 0 on success.
2817 */
2818 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2819 void __user *buffer, size_t *lenp, loff_t *ppos)
2820 {
2821 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2822 do_proc_dointvec_ms_jiffies_conv, NULL);
2823 }
2824
2825 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2826 void __user *buffer, size_t *lenp, loff_t *ppos)
2827 {
2828 struct pid *new_pid;
2829 pid_t tmp;
2830 int r;
2831
2832 tmp = pid_vnr(cad_pid);
2833
2834 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2835 lenp, ppos, NULL, NULL);
2836 if (r || !write)
2837 return r;
2838
2839 new_pid = find_get_pid(tmp);
2840 if (!new_pid)
2841 return -ESRCH;
2842
2843 put_pid(xchg(&cad_pid, new_pid));
2844 return 0;
2845 }
2846
2847 #else /* CONFIG_PROC_FS */
2848
2849 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2850 void __user *buffer, size_t *lenp, loff_t *ppos)
2851 {
2852 return -ENOSYS;
2853 }
2854
2855 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2856 void __user *buffer, size_t *lenp, loff_t *ppos)
2857 {
2858 return -ENOSYS;
2859 }
2860
2861 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2862 void __user *buffer, size_t *lenp, loff_t *ppos)
2863 {
2864 return -ENOSYS;
2865 }
2866
2867 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2868 void __user *buffer, size_t *lenp, loff_t *ppos)
2869 {
2870 return -ENOSYS;
2871 }
2872
2873 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2874 void __user *buffer, size_t *lenp, loff_t *ppos)
2875 {
2876 return -ENOSYS;
2877 }
2878
2879 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2880 void __user *buffer, size_t *lenp, loff_t *ppos)
2881 {
2882 return -ENOSYS;
2883 }
2884
2885 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2886 void __user *buffer, size_t *lenp, loff_t *ppos)
2887 {
2888 return -ENOSYS;
2889 }
2890
2891 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2892 struct file *filp,
2893 void __user *buffer,
2894 size_t *lenp, loff_t *ppos)
2895 {
2896 return -ENOSYS;
2897 }
2898
2899
2900 #endif /* CONFIG_PROC_FS */
2901
2902
2903 #ifdef CONFIG_SYSCTL_SYSCALL
2904 /*
2905 * General sysctl support routines
2906 */
2907
2908 /* The generic sysctl data routine (used if no strategy routine supplied) */
2909 int sysctl_data(struct ctl_table *table,
2910 void __user *oldval, size_t __user *oldlenp,
2911 void __user *newval, size_t newlen)
2912 {
2913 size_t len;
2914
2915 /* Get out of I don't have a variable */
2916 if (!table->data || !table->maxlen)
2917 return -ENOTDIR;
2918
2919 if (oldval && oldlenp) {
2920 if (get_user(len, oldlenp))
2921 return -EFAULT;
2922 if (len) {
2923 if (len > table->maxlen)
2924 len = table->maxlen;
2925 if (copy_to_user(oldval, table->data, len))
2926 return -EFAULT;
2927 if (put_user(len, oldlenp))
2928 return -EFAULT;
2929 }
2930 }
2931
2932 if (newval && newlen) {
2933 if (newlen > table->maxlen)
2934 newlen = table->maxlen;
2935
2936 if (copy_from_user(table->data, newval, newlen))
2937 return -EFAULT;
2938 }
2939 return 1;
2940 }
2941
2942 /* The generic string strategy routine: */
2943 int sysctl_string(struct ctl_table *table,
2944 void __user *oldval, size_t __user *oldlenp,
2945 void __user *newval, size_t newlen)
2946 {
2947 if (!table->data || !table->maxlen)
2948 return -ENOTDIR;
2949
2950 if (oldval && oldlenp) {
2951 size_t bufsize;
2952 if (get_user(bufsize, oldlenp))
2953 return -EFAULT;
2954 if (bufsize) {
2955 size_t len = strlen(table->data), copied;
2956
2957 /* This shouldn't trigger for a well-formed sysctl */
2958 if (len > table->maxlen)
2959 len = table->maxlen;
2960
2961 /* Copy up to a max of bufsize-1 bytes of the string */
2962 copied = (len >= bufsize) ? bufsize - 1 : len;
2963
2964 if (copy_to_user(oldval, table->data, copied) ||
2965 put_user(0, (char __user *)(oldval + copied)))
2966 return -EFAULT;
2967 if (put_user(len, oldlenp))
2968 return -EFAULT;
2969 }
2970 }
2971 if (newval && newlen) {
2972 size_t len = newlen;
2973 if (len > table->maxlen)
2974 len = table->maxlen;
2975 if(copy_from_user(table->data, newval, len))
2976 return -EFAULT;
2977 if (len == table->maxlen)
2978 len--;
2979 ((char *) table->data)[len] = 0;
2980 }
2981 return 1;
2982 }
2983
2984 /*
2985 * This function makes sure that all of the integers in the vector
2986 * are between the minimum and maximum values given in the arrays
2987 * table->extra1 and table->extra2, respectively.
2988 */
2989 int sysctl_intvec(struct ctl_table *table,
2990 void __user *oldval, size_t __user *oldlenp,
2991 void __user *newval, size_t newlen)
2992 {
2993
2994 if (newval && newlen) {
2995 int __user *vec = (int __user *) newval;
2996 int *min = (int *) table->extra1;
2997 int *max = (int *) table->extra2;
2998 size_t length;
2999 int i;
3000
3001 if (newlen % sizeof(int) != 0)
3002 return -EINVAL;
3003
3004 if (!table->extra1 && !table->extra2)
3005 return 0;
3006
3007 if (newlen > table->maxlen)
3008 newlen = table->maxlen;
3009 length = newlen / sizeof(int);
3010
3011 for (i = 0; i < length; i++) {
3012 int value;
3013 if (get_user(value, vec + i))
3014 return -EFAULT;
3015 if (min && value < min[i])
3016 return -EINVAL;
3017 if (max && value > max[i])
3018 return -EINVAL;
3019 }
3020 }
3021 return 0;
3022 }
3023
3024 /* Strategy function to convert jiffies to seconds */
3025 int sysctl_jiffies(struct ctl_table *table,
3026 void __user *oldval, size_t __user *oldlenp,
3027 void __user *newval, size_t newlen)
3028 {
3029 if (oldval && oldlenp) {
3030 size_t olen;
3031
3032 if (get_user(olen, oldlenp))
3033 return -EFAULT;
3034 if (olen) {
3035 int val;
3036
3037 if (olen < sizeof(int))
3038 return -EINVAL;
3039
3040 val = *(int *)(table->data) / HZ;
3041 if (put_user(val, (int __user *)oldval))
3042 return -EFAULT;
3043 if (put_user(sizeof(int), oldlenp))
3044 return -EFAULT;
3045 }
3046 }
3047 if (newval && newlen) {
3048 int new;
3049 if (newlen != sizeof(int))
3050 return -EINVAL;
3051 if (get_user(new, (int __user *)newval))
3052 return -EFAULT;
3053 *(int *)(table->data) = new*HZ;
3054 }
3055 return 1;
3056 }
3057
3058 /* Strategy function to convert jiffies to seconds */
3059 int sysctl_ms_jiffies(struct ctl_table *table,
3060 void __user *oldval, size_t __user *oldlenp,
3061 void __user *newval, size_t newlen)
3062 {
3063 if (oldval && oldlenp) {
3064 size_t olen;
3065
3066 if (get_user(olen, oldlenp))
3067 return -EFAULT;
3068 if (olen) {
3069 int val;
3070
3071 if (olen < sizeof(int))
3072 return -EINVAL;
3073
3074 val = jiffies_to_msecs(*(int *)(table->data));
3075 if (put_user(val, (int __user *)oldval))
3076 return -EFAULT;
3077 if (put_user(sizeof(int), oldlenp))
3078 return -EFAULT;
3079 }
3080 }
3081 if (newval && newlen) {
3082 int new;
3083 if (newlen != sizeof(int))
3084 return -EINVAL;
3085 if (get_user(new, (int __user *)newval))
3086 return -EFAULT;
3087 *(int *)(table->data) = msecs_to_jiffies(new);
3088 }
3089 return 1;
3090 }
3091
3092
3093
3094 #else /* CONFIG_SYSCTL_SYSCALL */
3095
3096
3097 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3098 {
3099 struct __sysctl_args tmp;
3100 int error;
3101
3102 if (copy_from_user(&tmp, args, sizeof(tmp)))
3103 return -EFAULT;
3104
3105 error = deprecated_sysctl_warning(&tmp);
3106
3107 /* If no error reading the parameters then just -ENOSYS ... */
3108 if (!error)
3109 error = -ENOSYS;
3110
3111 return error;
3112 }
3113
3114 int sysctl_data(struct ctl_table *table,
3115 void __user *oldval, size_t __user *oldlenp,
3116 void __user *newval, size_t newlen)
3117 {
3118 return -ENOSYS;
3119 }
3120
3121 int sysctl_string(struct ctl_table *table,
3122 void __user *oldval, size_t __user *oldlenp,
3123 void __user *newval, size_t newlen)
3124 {
3125 return -ENOSYS;
3126 }
3127
3128 int sysctl_intvec(struct ctl_table *table,
3129 void __user *oldval, size_t __user *oldlenp,
3130 void __user *newval, size_t newlen)
3131 {
3132 return -ENOSYS;
3133 }
3134
3135 int sysctl_jiffies(struct ctl_table *table,
3136 void __user *oldval, size_t __user *oldlenp,
3137 void __user *newval, size_t newlen)
3138 {
3139 return -ENOSYS;
3140 }
3141
3142 int sysctl_ms_jiffies(struct ctl_table *table,
3143 void __user *oldval, size_t __user *oldlenp,
3144 void __user *newval, size_t newlen)
3145 {
3146 return -ENOSYS;
3147 }
3148
3149 #endif /* CONFIG_SYSCTL_SYSCALL */
3150
3151 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3152 {
3153 static int msg_count;
3154 int name[CTL_MAXNAME];
3155 int i;
3156
3157 /* Check args->nlen. */
3158 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3159 return -ENOTDIR;
3160
3161 /* Read in the sysctl name for better debug message logging */
3162 for (i = 0; i < args->nlen; i++)
3163 if (get_user(name[i], args->name + i))
3164 return -EFAULT;
3165
3166 /* Ignore accesses to kernel.version */
3167 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3168 return 0;
3169
3170 if (msg_count < 5) {
3171 msg_count++;
3172 printk(KERN_INFO
3173 "warning: process `%s' used the deprecated sysctl "
3174 "system call with ", current->comm);
3175 for (i = 0; i < args->nlen; i++)
3176 printk("%d.", name[i]);
3177 printk("\n");
3178 }
3179 return 0;
3180 }
3181
3182 /*
3183 * No sense putting this after each symbol definition, twice,
3184 * exception granted :-)
3185 */
3186 EXPORT_SYMBOL(proc_dointvec);
3187 EXPORT_SYMBOL(proc_dointvec_jiffies);
3188 EXPORT_SYMBOL(proc_dointvec_minmax);
3189 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3190 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3191 EXPORT_SYMBOL(proc_dostring);
3192 EXPORT_SYMBOL(proc_doulongvec_minmax);
3193 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3194 EXPORT_SYMBOL(register_sysctl_table);
3195 EXPORT_SYMBOL(register_sysctl_paths);
3196 EXPORT_SYMBOL(sysctl_intvec);
3197 EXPORT_SYMBOL(sysctl_jiffies);
3198 EXPORT_SYMBOL(sysctl_ms_jiffies);
3199 EXPORT_SYMBOL(sysctl_string);
3200 EXPORT_SYMBOL(sysctl_data);
3201 EXPORT_SYMBOL(unregister_sysctl_table);
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